1. Field of Invention
The present invention relates to a static memory. More particularly, the present invention relates to magnetoresistive random access memory (MRAM).
2. Description of Related Art
Magnetoresistive random access memory is a type of non-volatile memory with fast programming time and high density. A MRAM cell has two ferromagnetic layers separated by a non-magnetic layer. Information is stored as directions of magnetization vectors in the two ferromagnetic layers.
In conventional MRAM of a standard structural design, a single via is utilized for each GMR (Giant Magnetoresistance) memory bit end, and a metal is deposited into each via. However, the via in such conventional design is usually small, which results in residue remained inside the via after etching. In addition, the smaller via also causes unfavorable electrical contact between two adjacent GMR memory bits.
For the forgoing reasons, there is a need for developing a method and a structure to improving the contact of two adjacent GMR memory bit.